The present invention relates to a grade detecting apparatus for vehicles, which detects from the atmospheric pressure difference the grade of a road on which the vehicle is running.
Known measuring apparatus are of mechanical construction so that the apparatus include for example a weight whose vertical line is used as a reference line to detect the grade of a vehicle, and thus there is a disadvantage that during the running of the vehicle the grade of the road cannot be measured accurately due to the vibrations as well as the forward and backward accelerations of the vehicle and it is also impossible to accurately measure the grade if the vehicle is inclined due to the goods carried by the vehicle or the occupants.